Self spotting barbell press

ABSTRACT

A self-spotting barbell press is composed of an adjustable bench and uprights located on either side of the bench adjacent the lifters upper body. Barbell support arms extend from the uprights into the barbell&#39;s pathway and have the ability to slide up and down to contact the barbell and decrease the weight exerted on the exerciser. A single hydraulic cylinder in conjunction with a pulley system provides force to each lifting arm, which is depressed below the barbell&#39;s path before use. When assistance is needed, the weightlifter places a three-way valve into a valve position that allows hydraulic fluid under pressure to flow from an accumulator tank to a hydraulic cylinder with push-rod that causes the barbell support arms to ascend removing a user-determined amount of weight from the barbell. If the total amount of weight is not to be removed, the user can continue performing repetitions with assistance from the hydraulic system. Another valve position allows only upward movement should the exerciser fail.

This application is a continuation-in-part of U.S. patent application Ser. No. 11/364,276, filed on Feb. 28, 2006, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present invention generally relates to free weight exercise equipment, and in particular to an improved self-spotting bench press.

(2) Description of the Prior Art

The use of barbells, i.e., free weights, for conditioning and enhancement of the body's musculature is widely practiced by a variety of people. Often, these people prefer to weight lift in the privacy of their home, and when they feel like weight lifting.

Most often weight training is executed with a spotter, i.e., someone who can assist the lifter when they become fatigued or are having difficulty or are about to drop the weight. Style, communication, consistency and reaction time are all factors that vary when being spotted. These factors are major deterrents to using a human spotter. However, to weight lift without a spotter may be dangerous to the weight lifter. There is a significant danger of serious injury due to fatigue or improper technique unless a spotter is present to grab the barbell to prevent the barbell from dropping on the weight lifter. This danger exists in situations from private to professional weight lifting.

The danger of crushing one's chest performing the bench press exercise is a great concern. U.S. Pat. No. 6,746,379 to Brawner (2004) shows a device that lifts the weight from the lifter's chest using multiple hydraulic cylinders. While this device removes the weight it does so at considerable cost since multiple cylinders and the hydraulic components to support them are required. U.S. Pat. No. 5,989,164 to Kullman et al (1999) shows a device that lifts the weight from the lifter's chest. While this device removes the weight from the lifter's chest, it utilizes cables attached to the lifting weight that increase setup time and can cause increased or decreased resistance due to contact with the barbell. U.S. Pat. No. 6,926,648 to Capizzo (2005) shows a device that also lifts the weight from the lifter's chest using a motor. This device lacks the ability to adjust the amount of assist, and rate of lift to each lifter's preference. U.S. Pat. No. 6,632,159 to Slattery (2003) describes a spotting machine that requires power to operate an electric motor that limits the machine to an area supplied with a power source.

All the machines heretofore known suffer from one or more of the following disadvantages:

a. Using multiple hydraulic cylinders. The lifting functionality of U.S. Pat. No. 6,746,379 to Brawner (2004) can be achieved without the use of multiple cylinders.

b. When using multiple hydraulic cylinders connected to the same pressure supply the cylinders don't always ascend at the same rate.

c. Exercisers regularly lean weight plates against the uprights of the exercise bench. Prior art using upright mounted hydraulic cylinders risk cylinder damage and hydraulic leaks due to this tendency.

d. Require lifting mechanism adjustment such that the lifting range of the mechanism is consistent with the lifting range of the exerciser.

e. Not being adjustable to suit each individual lifter's spotting preference, such as whether the spotting mechanism should assist the lifter by removing a fraction of the weight, remove all the weight, or not be used at all, and rate at which the spotting mechanism lifts the weight.

f. Not enabling the lifter to continue repetitions while being assisted by the spotting device and still having the ability to lock the spotting device preventing the weight from falling on or crushing the lifter.

g. Requiring electrical power.

h. Using barbell attachments such as cables that impede motion.

i. Using a greater quantity of material and being significantly larger and therefore heavier than traditional bench presses. This is more costly and discourages their use in private homes.

j. Not enabling the lifter to use the device with a human spotter.

SUMMARY OF THE INVENTION

The present invention relates to a safety device for supporting a weight bar (barbell) above an exerciser, and to an apparatus comprised of the safety device in combination with free-weight exercise equipment (such as, but not limited to a bench press or squat rack).

Generally, the apparatus is comprised of first and second placed elongated uprights positionable on opposite sides of the head or upper end of the weightlifting bench, or of the squatting area. Note that the weightlifting bench position within the plane of the uprights is the position from which the squat exercise is performed should the apparatus not be fitted with a bench. Each of the uprights includes a slotted, elongated outer housing, an elongated slide bar that is longitudinally aligned within the housing, and a sleeve slideable on the slide bar between raised and lowered positions. The slideable sleeve and slide bar can be replaced by a shuttle type slide that does not require a slide bar/ball bushing slide. Such a shuttle type slide would have wheels and traverse up and down the upright using the upright as a track. Affixed to the slideable assembly of each upright is a cable of sufficient strength and flexibility to convey hydraulic cylinder force to the slide assembly. In other words, a first cable is included for the first upright and a second cable is included for the second upright. For the purposes of this disclosure, the term cable includes straps, cords and wires.

Conventional pulley wheels located at each end of the uprights are for directing the cables in a plane parallel with the uprights and then in the direction of the hydraulic cylinder push-rod. This pulley and cable arrangement allows the conversion and relocation of linear push-rod movement into linear slide assembly movement in each upright. A horizontal barbell support arm is attached to the sleeve and extends outwardly from the housing through the first slot in the direction of the bench or perpendicular to the vertical plane that passes through the barbell. The barbell support arms are parallel and lie in a horizontal plane above the bench or squatting position, with the arm intersecting the path of the barbell when it is lifted.

A single hydraulic cylinder is positioned within an enclosure that extends between the first and second uprights in an area that is typically used by a human spotter. The hydraulic cylinder is of conventional design and is comprised of a tubular section with a hydraulic fluid inlet at one end. At the other end, a push-rod having inner and outer ends projects outwardly from the cylinder. The inner end of the push-rod is connected to a piston within the cylinder. When hydraulic fluid enters the interior of the tubular section, the push-rod extends outwardly from the cylinder. The outer end of the push-rod includes a pulley wheel with axle of sufficient strength and size to accommodate the cables having their first ends attached to the slideable assembly. The second ends of the cables are attached to the distal end of the cylinder. However, the cable second ends could be fastened to other locations and achieve the same result of providing an anchor point for each cable. An idler pulley is mounted to the distal end of the cylinder. The idler pulley is free to rotate within a plane parallel to the extendable push-rod such that the cable originating from the upright in the direction that the cylinder push-rod extends can be redirected. From their anchor point on the distal side of the cylinder, each cable will extend in the direction of, and around the pulley wheel on the extendable push-rod, then extend back in the direction of, and parallel to the cylinder. At this point, the first cable will round the pulley wheel on the distal end of the cylinder and be directed toward the pulley wheel at the lower end of the first upright in the direction that the cylinder push-rod extends. The second cable will extend past the cylinder and be directed toward the pulley wheel at the lower end of the second upright. Preferably, the tubular section of the hydraulic cylinder is attached at each end to a cross member adjoining the first and second uprights. Thus, as the push-rod is extended under pressure of hydraulic fluid, the slideable sleeves and attached barbell support arms are urged to move in an upward direction. The cross member can also make up one side of the enclosure housing the hydraulic cylinder.

The combination of cables and pulleys with the single hydraulic cylinder and push-rod provides a unique mechanical advantage over the prior art. For example, the number and arrangement of pulleys can be selected to provide a fixed ratio of travel between the barbell supports and the stroke length of the push-rod. The preferred embodiment uses a cable and pulley arrangement that yields a two-inch travel for every inch of push-rod stroke, i.e., a 2:1 travel ratio. This allows for a shorter and less expensive hydraulic cylinder to be used as the system's actuator. Other travel ratios such as 3:1 could be selected. In fact, dependent upon the number and arrangement of pulleys used as well as their diameter, a practical travel ratio of push-rod travel to barbell support arm travel can be implemented from about 1:10 to 10:1.

A hydraulic fluid accumulator of conventional design stores the energy needed to raise a barbell weight from a weightlifter. Preferably, the accumulator is housed within the enclosure that houses the hydraulic cylinder.

Basically, the accumulator or “gas-oil” tank is comprised of a pressure housing or tank containing an air inlet above the level of a hydraulic fluid, and a hydraulic outlet beneath the hydraulic fluid level. For the purposes of this disclosure, hydraulic fluid is a non-compressible fluid such as oil. The present invention stores hydraulic fluid under pressure within the accumulator due to a pre-charge of compressed air that is also in the accumulator.

The accumulator can be pre-charged with gases other than air. For example, nitrogen gas would provide extended system life due to its inertness. Moreover, the accumulator can include a gas pressure relief valve and a connection above the hydraulic fluid level that allows the accumulator tank to be pressurized or charged with gas. There is also a hydraulic line connection below the lowest fluid level of the tank.

A pressure gauge in communication with the hydraulic fluid or gas inside of the accumulator is usable by the weightlifter to monitor the pre-charge accumulator pressure. The pressure gauge can be mechanical with an analog readout or electronic with a digital readout display.

A hydraulic plumbing system in communication with the accumulator tank and the hydraulic cylinder provides a means for control of the flow of hydraulic into and out of the accumulator and hydraulic cylinder. The plumbing system comprises hydraulic conduits in communication with at least one in-line check valve and a three-way ball valve. For the purpose of this disclosure, a check valve is a valve that allows fluid flow in only one direction. An important specification for a check valve is its cracking pressure, which is the pressure differential at which the check valve opens to allow unidirectional fluid flow.

A check valve that is suitable for the present apparatus has a body with a hollow interior that leads to a fluid inlet and a fluid outlet. The check valve's interior includes a valve seat and a spring loaded obstructor that shuts off fluid flow when the differential pressure between the fluid inlet and fluid outlet is less than the check valve's predetermined cracking pressure. When the differential pressure between the fluid inlet and fluid outlet becomes greater than the check valve's cracking pressure, the spring loaded obstructor backs away from the check valve seat allowing fluid to pass through the check valve from its inlet to its outlet.

For any embodiment of the present invention, the cracking pressure is preferably significantly below the lowest hydraulic fluid pressure of the accumulator. A check valve cracking pressure of less than twenty-five pounds-per-square inch (psi) is preferred for the present invention.

The present invention's preferred three-way ball valve is of conventional design with a body having first, second and third fluid ports. These ports are arranged in a T geometry, with the first and third ports being located at the ends of the top of the T, and the second port being located at the bottom of the T stem.

A rotatable ball having a central T-shaped fluid passageway fits snugly within a spherical shaped valve seat within the ball valve body. A lever in mechanical communication with the ball is for turning the ball and its T-shaped fluid passageway to a plurality of ball valve positions for controlling the fluid flow and direction of fluid flow through the first, second and third fluid ports. The preferred three-way ball valve belongs to a family of valves known as quarter turn valves, i.e., each valve position is separated by ninety degrees from its previous position.

In a first embodiment of the invention, the accumulator tank is in fluidic communication with the hydraulic cylinder through two check valves and the three-way valve. In this embodiment, a fluid conduit section connects the accumulator tank with the ball valve's second port. Another conduit section connects the ball valve's first port to the inlet of a first check valve. The outlet of the first check valve is connected to the hydraulic port of the hydraulic cylinder by another section of conduit. Yet another conduit section connects the hydraulic cylinder port to the inlet of a second check valve, which has its outlet coupled to port three of the ball valve.

In this first embodiment, hydraulic fluid flow through ball valve port one can only flow in the direction of the first check valve's inlet. Moreover, hydraulic fluid flow can only flow through port three from the outlet of the second check valve. Depending on the valve position of the ball valve's T passageway, hydraulic fluid can flow through the ball valve's port two either in the direction of the accumulator or in the direction of the hydraulic cylinder.

Moreover, in this first embodiment a first valve position places the ball valve's T-passageway in fluidic communication with valve ports three and two. The first valve position lets fluid flow from the cylinder into the accumulator allowing the barbell support arms to descend towards their lowered position at a predetermined rate under the force of gravity.

In a second valve position of the first embodiment, the ball valve's T-passageway is in fluidic communication with all three ball valve ports. This second valve position allows fluid flow from and to the cylinder, thereby allowing the barbell support arms to move upward and downward. When this second valve position is engaged after the barbell support arms have lowered after engaging the first valve position, the hydraulic fluid under pressure in the accumulator tank will cause the barbell support arms to rapidly ascend to “spot” the lifting of the weight by a weightlifter. The second valve position allows the weightlifter to continue his exercise with the barbell support arms removing a predetermined amount of weight from the weightlifters burden. The desired amount of weight removed is adjustable by varying the amount of hydraulic pressure delivered by the accumulator tank.

A third valve position of the first embodiment allows fluid to flow into the cylinder, thus the barbell support arms can only move upward. Moreover, this third valve position traps hydraulic fluid in the hydraulic cylinder. Therefore, a supported barbell weight will not fall even if the pressure in the accumulator falls below what would be needed to support the same barbell weight with another valve position. The weightlifter engages the third valve position at the lowest point of the last assisted weightlifting repetition. As a result, the weightlifter can lift the supported barbell from the barbell support arms from a bench pressing position without fear of being crushed by the barbell in case the weightlifter were to fatigue and release the barbell. The third valve position is the last valve position needed to complete the weightlifter's exercise routine because this valve position maintains the barbell weight at a position high enough for the weightlifter to exit a barbell press position. Moreover, the third valve position of this first embodiment is considered the “emergency” position, because it is used when the weightlifter becomes so fatigued that he is in danger of dropping the barbell and potentially injuring himself.

A fourth valve position of the first embodiment connects valve ports one and two only and serves no functional purpose other than being located near valve position one to restart a weightlifting exercise routine. The barbell support arms will lower, once the weightlifter moves the valve from the fourth position to the first position.

In a second embodiment of the invention, the accumulator tank is in fluidic communication with the hydraulic cylinder through a single check valve and a single three-way valve. In this embodiment, a fluid conduit section connects the accumulator tank with the ball valve's third port. Another conduit section connects the ball valve's second port to the inlet of a single check valve. The outlet of the check valve is connected to the hydraulic port of the hydraulic cylinder by another section of conduit. Yet another conduit section connects the hydraulic cylinder port directly to port one of the ball valve.

In this second embodiment, hydraulic fluid flow through ball valve port two can only flow in the direction of the check valve's inlet. Depending on the valve position of the ball valve's T passageway, hydraulic fluid can flow through the ball valve's port three either in the direction of the accumulator or in the direction of the hydraulic cylinder.

Moreover, in this second embodiment a first valve position places the ball valve's T-passageway in fluidic communication with all three ball valve ports. The first valve position lets fluid flow from the cylinder into the accumulator allowing the barbell support arms to descend towards their lowered position at a predetermined rate under the force of gravity.

In a second valve position, the ball valve's T-passageway is in fluidic communication with ball valve ports one and two. This second valve position prevents fluid flow from and to the cylinder, thereby locking the barbell support arms in a fixed position. In other words, no hydraulic fluid can flow into or out of the accumulator through ball valve port three.

A third valve position allows fluid to flow into and out of the cylinder. In this third valve position, the barbell support arms can travel either upwardly or downwardly. The barbell support arms will travel upwardly in response to the weightlifter's lifting of the barbell weight. In contrast, the barbell support arms will descend under the force of gravity as the weightlifter brings the barbell down to a start position.

A fourth valve position only allows fluid flow into the hydraulic cylinder, thereby urging the barbell support arms toward their raised position. The weightlifter typically engages this fourth valve position when the barbell support is at its lowest point of the last assisted weightlifting repetition. The fourth valve position is the last valve position needed to complete the weightlifter's exercise routine because this valve position maintains the barbell weight at a position high enough for the weightlifter to exit a barbell press position. The fourth valve position of this second embodiment is considered the “emergency” position, because it is used when the weightlifter becomes so fatigued that he is in danger of dropping the barbell and potentially injuring himself.

The apparatus may include a user support bench, which is preferably of sufficient length to support the user's head and torso. When combined with the safety device, the head of the bench can be raised and lowered. For example, a vertically adjustable bench support bar may extend from the frame of the bench, with the head of the bench being supported on the support bar. An additional horizontal mounting bar may be used to attach the uprights to each other. The uprights may also include barbell rests attachable at various locations along the upright housings.

When combined with the safety device, the apparatus may further include a sufficiently vacant area between the uprights for giving the user space or weight lifting area to perform squat exercises. This space is also available for placing detached seats, benches, or other exercise enabling supports. An additional horizontal mounting bar may be used to attach the uprights to each other in such a way that it does not interfere with the squat exercise, or placement and use of exercise enabling devices. The uprights may also include barbell rests attachable at various locations along the upright housings.

The apparatus may further include the incorporation of the upright supports into a cage that prevents the lifting weight from moving outside the area above the barbell support arms. When combined with the safety device, the barbell support arms may extend into the lifting cage with sufficient depth and movement to support the squat exercise or any other bar based exercises performed within the cage.

In order to control the position of the barbell support arms, the apparatus includes a controller or actuator accessible by the user when reclined on the bench or standing between the uprights. This actuator, which may be foot or hand operated, is used to position the T-shaped passageway of the hydraulic three-way ball valve into one of its plurality of valve positions. For example, the actuator is used to place the T-shaped passageway of the three-way ball valve into a valve position that causes hydraulic fluid to enter the hydraulic cylinder whenever the weightlifter needs assistance. As a result, the push-rod of the hydraulic cylinder is extended, raising the barbell support arms and lifting the barbell away from the user. The hydraulic three-way ball valve may be partially opened to release a limited volume of fluid to slowly raise the barbell, or fully opened to raise the barbell quickly. If the actuator is hand operated, it is preferred that it be a trigger type actuator. This trigger is important because anyone doing squats on the bench is required to stand between the uprights, thereby making foot operation of the actuator impractical.

It is important to note that the hydraulic system is operated as a closed system in that there is no exhaust like is common with some pneumatic systems. In fact, the present system can work indefinitely with only one pre-charge of the accumulator if no adjusts to pressure are desired. Further objects and advantages of the present invention will become apparent from a consideration of the drawings and ensuing description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 Self Spotting Safety Bench Press Composite

FIG. 2 Inner Front Side of Upright

FIG. 3 Upright Internal Attachments

FIG. 4 Adjustable Weight Rest

FIG. 5 Adjustable Weight Rest

FIG. 6 Hydraulic & Pneumatic Power System with Transmission

FIG. 7 A First Embodiment Hydraulic System Diagram Showing a First Valve Position

FIG. 8 A First Embodiment Hydraulic System Diagram Showing a Second Valve Position

FIG. 9 A First Embodiment Hydraulic System Diagram Showing a Third Valve Position

FIG. 10 A First Embodiment Hydraulic System Diagram Showing a Fourth Valve Position

FIG. 11 A Second Embodiment Hydraulic System Diagram Showing a First Valve Position

FIG. 12 A Second Embodiment Hydraulic System Diagram Showing a Second Valve Position

FIG. 13 A Second Embodiment Hydraulic System Diagram Showing a Third Valve Position

FIG. 14 A Second Embodiment Hydraulic System Diagram Showing a Fourth Valve Position

DETAILED DESCRIPTION OF THE INVENTION

In the following description, terms such as horizontal, upright, vertical, above, below, beneath, and the like, are used solely for the purpose of clarity in illustrating the invention, and should not be taken as words of limitation. The drawings are for the purpose of illustrating the invention and are not intended to be to scale.

FIG. 1 shows a composite drawing of the device. There are two uprights (1 a, 1 b) parallel to each other and tilted slightly away from the longer side of the seat (7). Two adjustable weight rests (16 a, 16 b) are located on the inner side of each upright. Protruding from the front of each upright (1 a, 1 b) is a lifting arm (2 a, 2 b) that extends perpendicular to gravity and in the direction of the seat (7) and adjustable seat frame (30). Each upright (1 a, 1 b) has a support (29 a, 29 b) and is connected to the other via a cross bar that is a member of an enclosure (6). Mounted inside enclosure (6) is an accumulator (8) (see FIG. 6) and a hydraulic cylinder (9) (see FIG. 6). Attached to the center of the cross bar of enclosure (6) is the upper end of the adjustable seat (7) frame. Attached close to the floor at the foot end of the seat (7) is an actuator (10).

FIG. 2 focuses on upright (1 b). The inner side and front side of upright (1 b) contains weight rest support holes (21) extending partially down the upright. The front of the upright (1 b) to the right of the holes contains a lifting arm slot (22). Contained within the upright are centering holes for holding the slide bar (3 b) (please see FIGS. 3 and 6).

FIG. 3 shows the parts an upright (1 b) contains without the upright itself included. The slide bar (3 b) nearly extends the full length of the upright (1 b) and is held in place by centering plates (24 b). Mounted on the slide bar (3 b) is the slide (4 b) that contains bearings (5 b) at either end. Attached to the slide (4 b) is a cable (27 b) and lifting arm (2 b). An upright base Pulley (19 b) and top pulley (20 b) are located at the extents of the upright (1 b). The upright cap (23 b) and floor plate (25 b) are at opposing ends of the upright.

FIGS. 4 and 5 show the adjustable weight rest (16 b). This piece is “u” shaped to partially wrap around an upright (1 b). It contains two mounting pins (31). The first pin is located on the backside of the front plate containing the barbell support extension. The second pin is located on the side plate to extend into the inner weight rest support holes (21). Pin location coincides with the weight rest support holes (21). Pin location allows the front pin to slide into the rest support hole (21) when the adjustable weight rest (16 b) is rotated clockwise ninety degrees. Once the first pin is seated in the support hole, rotation of the adjustable weight rest (16 b) ninety degrees counter clock wise (with the front pin within the support hole (21) being the axis of rotation) seats the inner pin in the inner rest support hole (21).

FIG. 6 shows the hydraulic cylinder (9) and accumulator (8) that powers the self-spotting bench. The rate at which barbell support arms ascends or descend is adjustable by way of a hydraulic fluid flow restrictor valve (12). Uprights (1 a, 1 b) straddle hydraulic cylinder (9).

As shown in FIG. 6, one end of each cable (27 a, 27 b) is attached to hydraulic cylinder (9), which is positioned adjacent to accumulator (8). Cables (27 a, 27 b) rounds a pulley (17) that is attached to the distal end of a push-rod (11) where they proceed toward the cylinder pulley (18). At the cylinder pulley (18), cables (27 a, 27 b) separate for the uprights (1 a, 1 b). Cable (27 a) proceeds towards the bottom of its respective upright (1 a) and cable (27 b) rounds the cylinder pulley (18) then proceeds toward its respective upright (1 b). Next, cables (27 a, 27 b) round the upright base pulleys (19 a, 19 b), and round upright top pulleys (20 a, 20 b) to connect with the slides (4 a, 4 b).

FIGS. 7-10 illustrate a first embodiment of a hydraulic plumbing system (32) of the present invention. In this first embodiment, the accumulator tank (8) is in fluidic communication with the hydraulic cylinder (9) through two check valves (36), (38) and a single three-way valve (40). In this embodiment, a fluid conduit section (42) connects accumulator tank (8) with the ball valve's second port (46). Another conduit section (50) connects the ball valve's first port (44) to the first check valve's inlet (52). The first check valve's outlet (54) is connected to the hydraulic cylinder's hydraulic port (56) by another section of conduit (58). Yet another conduit section (60) connects hydraulic cylinder port (56) to the inlet (62) of second check valve (38), which has its outlet (64) coupled to port three (48) of ball valve (40).

In this first embodiment, hydraulic fluid (66) can only flow through ball valve port one (44) in the direction of the first check valve's inlet (52). Moreover, hydraulic fluid (66) can only flow through port three (48) from the second check valve's outlet (64). Depending on the valve position of the ball valve's T passageway (68), hydraulic fluid (66) can flow through the ball valve's port two (46) either in the direction of accumulator (8) or in the direction of hydraulic cylinder (9).

Moreover, as depicted in FIG. 7 a first valve position places ball valve's T-passageway (68) in fluidic communication with valve ports three (48) and two (46). The first valve position lets fluid flow from cylinder (9) into accumulator (8) allowing push-rod (11) with attached pulley (17) to retract, thereby allowing the barbell support arms (2 a, 2 b), shown in FIGS. 1 and 6, to descend towards their lowered position at a predetermined rate under the force of gravity.

FIG. 8 depicts a second valve position of the first embodiment. In the second valve position, the ball valve's T-passageway (68) is in fluidic communication with all three ball valve ports (44), (46) and (48). This second valve position allows hydraulic fluid (66) to flow from and to cylinder (9), thereby allowing push-rod (11) to extend and retract allowing barbell support arms (2 a, 2 b) of FIGS. 1 and 6 to move up and down in synchronization with barbell (26) of FIG. 1 as the weightlifter moves the barbell up and down. When this second valve position is engaged after the barbell support arms (2 a, 2 b) of FIGS. 1 and 6 have lowered in response to the first valve position, the hydraulic fluid under pressure in accumulator tank (8) will cause the barbell support arms (2 a, 2 b) to rapidly ascend to “spot” the lifting of barbell 26 by the weightlifter. The second valve position allows the weightlifter to continue his exercise with the barbell support removing a predetermined amount of weight from the weightlifters burden. The desired amount of weight removed is adjustable by varying the amount of hydraulic pressure delivered by accumulator tank (8).

FIG. 9 depicts a third valve position of the first embodiment. This third valve position only allows hydraulic fluid to flow into cylinder (8), thus push-rod (11) can only extend to urge barbell support arms (2 a, 2 b) of FIGS. 1 and 6 upward. Moreover, this third valve position traps hydraulic fluid (66) in hydraulic cylinder (9). Therefore, supported barbell (26) shown in FIG. 1 will not fall even if the pressure in accumulator tank (8) falls below what would be needed to support barbell weight (26) with another valve position. The weightlifter engages the third valve position at the lowest point of the last assisted weightlifting repetition. As a result, the weightlifter can lift supported barbell (26) of FIG. 1 from barbell support arms (2 a, 2 b) from a bench pressing position without fear of being crushed by barbell (26) in case the weightlifter were to fatigue and drop barbell (26). The third valve position is the last valve position needed to complete the weightlifter's exercise routine because this valve position maintains barbell (26) at a position high enough for the weightlifter to exit a barbell press position.

FIG. 10 shows a fourth valve position of the first embodiment. This fourth valve position connects valve ports one (44) and two (46) only. Therefore, this fourth valve position serves no functional purpose other than being located near the first valve position for restarting a weightlifting exercise routine. The barbell support will lower, once the weightlifter moves the valve from the fourth position to the first position.

FIGS. 11-14, depict a second embodiment of a hydraulic plumbing system (74) of the present invention. In this second embodiment, accumulator tank (8) is in fluidic communication with hydraulic cylinder (9) through a single check valve (80) and a single three-way valve (82). In this embodiment, a fluid conduit section (84) connects accumulator tank (8) with the ball valve's third port (86). Another conduit section (88) connects the ball valve's second port (90) to the inlet (92) of check valve (80). The outlet (94) of the check valve (80) is connected to a hydraulic port (96) of a hydraulic cylinder (9) by another conduit section (98). Yet another conduit section (100) connects hydraulic cylinder port (96) directly to port one (102) of ball valve (82).

In this second embodiment, hydraulic fluid (104) can only flow through ball valve port two (90) in the direction of check valve inlet (92). Depending on the valve position of the ball valve's T passageway (106), hydraulic fluid can flow through the ball valve's port three (86) either in the direction of accumulator (8) or in the direction of hydraulic cylinder (9).

As shown in FIG. 11, a first valve position places the ball valve's T-passageway (106) in fluidic communication with all three ball valve ports (86), (90) and (102). The first valve position lets hydraulic fluid 104 flow from cylinder (9) into accumulator (8) allowing the push-rod (11) and attached pulley (17) to retract thereby allowing the barbell support arms (2 a, 2 b) of FIGS. 1 and 2 to descend towards their lowered position at a predetermined rate under the force of gravity.

FIG. 12 depicts a second valve position. In this second valve position, the ball valve's T-passageway (106) is in fluidic communication with ball valve ports one (102) and two (90). This second valve position prevents hydraulic fluid (104) from flowing into or out of cylinder (9), thereby locking barbell support arms (2 a, 2 b) of FIGS. 1 and 2 in a fixed position.

FIG. 13 depicts a third valve position that allows hydraulic fluid (104) to flow into and out of cylinder (9). In this third valve position, the ball valve's T-passageway (106) is in fluidic communication with ball valve ports one (102) and three (86). When valve position three is engaged, push-rod (11) will extend rapidly to contact barbell (26) of FIG. 1 being held by the weightlifter. However, push-rod (11) will retract and extend to allow assisted weightlifting repetitions. The amount of assistance is determined by the pressure of hydraulic fluid (104) entering cylinder (9).

FIG. 14 depicts a fourth valve position that only allows fluid flow into the hydraulic cylinder (9), thereby urging barbell support arms (2 a, 2 b) of FIGS. 1 and 6 toward their raised position. In this fourth valve position, the ball valve's T-passageway (106) is in fluidic communication with ball valve ports two (90) and three (86). As a result, push-rod (11) can only extend. Thus, provided there is enough hydraulic pressure supplied by accumulator (8), push-rod (11) will urge the barbell support arms (2 a, 2 b) towards a fully raised position even if the weightlifter is completely fatigued. The weightlifter typically engages this fourth valve position when barbell support arms (2 a, 2 b) are at their lowest point of the last assisted weightlifting repetition. The fourth valve position is the last valve position needed to complete the weightlifter's exercise routine because this valve position maintains barbell (26) of FIG. 1 at a position high enough for the weightlifter to exit a barbell press position.

Operation

FIG. 1 shows barbell (26) being supported on barbell support arms (2 a, 2 b). However, weight rests (16 a, 16 b) can be used to hold barbell (26) while barbell support arms (2 a, 2 b) are being moved to a desired start position. The distance of barbell (26) from seat (7) (and therefore the lifter) can be adjusted by rotating each adjustable weight rest (16 a, 16 b) ninety degrees away from each upright (1 a, 1 b) using the front pin as a pivot point. After being rotated adjustable weight rests (16 a, 16 b) can be separated from each upright (1 a, 1 b) by moving it perpendicular to the upright in the direction the barbell support arms (2 a, 2 b) extend. The adjustable weight rests (16 a, 16 b) can be reattached in other locations performing the reverse of these instructions in any other weight rest support hole (21).

While barbell (26) is held on adjustable weight rests (16 a, 16 b) the lifter can place three-way valve (40) of FIG. 7 to its first position. This will allow the barbell support arms (2 a, 2 b) to only move downward. The lifter has two options as to how to depress the barbell support arms (2 a, 2 b). The first option is to get in the exercising position, remove the barbell (26) from the adjustable weight rests allowing the weight to lower and depress the barbell support arms (2 a, 2 b), and then start repetitions from the lowest point the bar traveled. The second option is to depress each barbell support arm (2 a, 2 b) by hand to a point where it will not interfere with the exercise until released.

If the lifter desires an increased or decreased assisting force exerted on barbell 26 by barbell support arms (2 a, 2 b), an air adjustment can be made to accumulator (8) by adding air 15 using a conventional air compressor (not shown) or by releasing air through accumulator tank valve (28). If the rate at which the lifting arm ascends is too slow or fast, the adjustable hydraulic fluid flow restrictor valve (12) can also be manipulated to suit user preference.

Repetitions are started once the barbell support arms are depressed and the equipment is adjusted to suit lifter's preferences. When the lifter needs a “spot”, three-way valve (40) is 20 placed in its second valve position. In this second valve position, compressed air in accumulator (8) acts as a spring and forces hydraulic fluid through check valve (36) and into hydraulic cylinder (9). Push-rod (11) then extends pulling cable (27 a, 27 b) causing each attached lifting arm (2 a, 2 b) to traverse upwardly. At some point, the barbell support arms (2 a, 2 b) contact barbell (26) and assist the lifter by removing some of the weight burden from the weightlifter. An opposite action occurs when the barbell support arms are being depressed (i.e. the hydraulic fluid in the hydraulic cylinder (9) is forced back into accumulator (8) where potential energy is stored by compressing trapped air in the accumulator.

Moreover, in this second valve position, the barbell support arms (2 a, 2 b) will follow the up and down of the weightlifter's barbell movements while providing an assisting force on barbell (26). This allows the lifter to continue by performing assisted repetitions when he/she could no longer lift the original weight unassisted.

When the lifter is no longer able to perform the assisted repetitions (or whenever else the lifter desires) three-way valve (40) is placed in its third valve position, which only allows hydraulic fluid to flow toward the cylinder (9). In this third valve position, barbell support arms (2 a, 2 b) will forcefully urge barbell (26) towards its raised position. This “emergency action” will allow the lifter to lift the barbell with assistance, and then prevent the barbell (26) from falling on the lifter when failure occurs.

The valve positions mentioned above are accomplished by use of actuator (10) that the exerciser manipulates with his/her lower leg or foot. Actuator (10) is connected to hydraulic valve (40) by way of actuator cables (15). When actuator (10) is kicked once in the direction of accumulator (8), three-way valve (40) will be placed in its first valve position. When kicked a second time, three-way valve (40) will be placed in its second valve position. A third valve position is achieved by kicking actuator (10) a third time. A fourth kick of actuator (10) places the three-way valve in a neutral valve position where the system can then be reset by either kicking actuator (10) a fifth time to place three-way valve (40) back into its first valve position.

Due to the stress the exerciser is experiencing during failure the exercisers leg or foot is likely to contact the actuator with significant force. The actuator therefore has a limited range of motion and does not transfer all of this energy to the valves. For the same reason the actuator is constructed with suitable smooth surface area as to not injure the exerciser when kicked. The design of the actuator (10) shown in FIG. 1 is not intended to limit the scope of this invention. A lanyard that attaches to the exerciser's leg or foot, or a switch that is mounted on the barbell is also feasible.

Thus the reader will see that the self-spotting safety bench press of this invention provides a dependable spotting machine that increases user safety with a minimum of components. The spotting speed and force exerted is fully adjustable to suit user preferences, as is weight rest position, and seat position. This machine has two spotting modes. The first mode allows the lifter to continue repetitions (up and down) assisted by the machine. The second mode only allows upward movement, preventing the weight from falling on the lifter. Furthermore, this machine requires no electrical power and is of a weight and size similar to traditional non-spotting bench presses. These attributes make this machine likely to be used in private and public gyms alike.

While the above description contains many specifics, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of one preferred embodiment thereof. Many other variations are possible. For example, the uprights described above do not have to be tilted away from the seat extension of the bench. Still another example is that the spotting device used with this machine is not to be limited to use with only one type of seat. A seat adjustable to various incline, decline and flat positions and seats in fixed positions are all types that can be used with this device. Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents. 

1. An apparatus for safely supporting a barbell comprising: a) first and second spaced uprights, each of said uprights including a barbell support arm having a raised position and a lowered position; b) a single hydraulic cylinder having a push-rod with extended and retracted positions, whereby movement of said push-rod between its extended and retracted positions raises and lowers each barbell support arm; c) a pre-charged accumulator tank having a pressure housing for storing hydraulic fluid under pressure; d) an actuatable valve having a plurality of valve positions for controlling the hydraulic fluid flow and direction of hydraulic fluid flow between said pre-charged accumulator tank and said hydraulic cylinder, whereby one of said plurality of valve positions allows fluid flow from said cylinder into said accumulator allowing said barbell support arms to descend towards said lowered position at a predetermined rate, and whereby another of said plurality of valve positions only allows fluid flow into said hydraulic cylinder thereby urging said barbell support arms toward their raised position; and e) at least one valve actuator for urging said actuatable valve into its plurality of valve positions.
 2. The apparatus of claim 1, wherein each of said uprights includes a slotted outer housing, a slide bar longitudinally aligned within said housing, and a sleeve slidable on said slide bar, said barbell support arm being attached to said sleeve and extending outwardly from said upright through said slot.
 3. The apparatus of claim 1, wherein the ratio between the range of push-rod travel, and the range of either barbell support arm travel is about 2:1.
 4. The apparatus of claim 1, further including an enclosure for said accumulator tank and said hydraulic cylinder, said enclosure extending between said uprights.
 5. The apparatus of claim 1, further including a check valve between said actuatable valve and said hydraulic cylinder, wherein said check valve only allows hydraulic fluid to flow into said hydraulic cylinder.
 6. The apparatus of claim 1, wherein said at least one valve actuator is positioned for access by a user's foot.
 7. The apparatus of claim 1, wherein said actuatable valve is a three-way valve having three fluid ports.
 8. An apparatus for safely supporting a barbell during weight lifting comprising: a) a weight bench having a head end and a lower end; b) first and second spaced, elongated uprights positioned on opposite sides of said bench head end, each of said uprights including a barbell support arm having a raised position and a lowered position, said uprights each having a top end with a pulley wheel; c) a single hydraulic cylinder having a push-rod with extended and retracted positions; d) first and second cables, each cable extending around a pulley from an anchored end to an opposed end in communication with said barbell support arm, whereby movement of said push-rod between its extended and retracted positions raises and lowers each barbell support arm; e) at least one pre-charged accumulator tank having a pressure housing for storing hydraulic fluid under pressure; f) an actuatable valve having a plurality of valve positions for controlling the fluid flow and direction of fluid flow between said pre-charged accumulator tank and said hydraulic cylinder, whereby a first valve position lets fluid flow from said cylinder into said accumulator allowing said barbell support arms to descend towards said lowered position, whereby a second valve position prevents fluid flow from and to said cylinder, thereby locking said barbell support arms in a fixed position, whereby a third valve position allows fluid to flow into and out of said cylinder, and whereby a fourth valve position only allows fluid flow into said hydraulic cylinder thereby urging said barbell support arms toward their raised position; and g) at least one valve actuator for urging said actuatable valve into its plurality of valve positions.
 9. The apparatus of claim 8, wherein the ratio between the range of push-rod travel, and the range of either barbell support arm travel is about 2:1.
 10. The apparatus of claim 8, wherein said at least one valve actuator is positioned adjacent the lower end of said bench.
 11. The apparatus of claim 8, further including a first check valve between said actuatable valve and said hydraulic cylinder, wherein said first check valve only allows hydraulic fluid to flow into said hydraulic cylinder.
 12. The apparatus of claim 11, further including a second check valve between said actuatable valve and said hydraulic cylinder, wherein said second check valve only allows hydraulic fluid to flow from said hydraulic cylinder.
 13. The apparatus of claim 8, wherein said actuatable valve is a three-way valve having three fluid ports and wherein each of said valve positions is separated by a quarter turn.
 14. The apparatus of claim 8, further including an enclosure for said accumulator tank and said hydraulic cylinder, said enclosure extending between said uprights.
 15. An apparatus for safely supporting a barbell during weight lifting comprising: a) a single hydraulic cylinder having a push-rod with extended and retracted positions; b) a pre-charged accumulator tank having a pressure housing for storing hydraulic fluid under pressure; c) first and second spaced, elongated uprights positioned to straddle said single hydraulic cylinder, each of said uprights including a slotted outer housing, a slide bar longitudinally aligned within said housing, a sleeve slidable on said slide bar between a raised position and a lowered position, and a horizontal barbell support attached to said sleeve and extending outwardly from said housing through said slot; d) first and second cables, each cable extending around a pulley from an anchored end to an opposed end attached to a slidable sleeve, whereby movement of said push-rod between its extended and retracted positions raises and lowers each slidable sleeve and barbell support arm; e) an actuatable valve having a plurality of positions for controlling the fluid flow and direction of fluid flow between said pre-charged accumulator tank and said hydraulic cylinder, whereby a first valve position lets fluid flow from said cylinder into said accumulator allowing said barbell support arms to descend towards said lowered position, whereby a second valve position prevents fluid flow from and to said cylinder, thereby locking said barbell support arm in a fixed position, and whereby a third valve position only allows fluid flow into said hydraulic cylinder thereby urging said barbell support arms toward their raised position; and f) at least one valve actuator for urging said actuatable valve into its plurality of valve positions.
 16. The apparatus of claim 15, wherein each of said actuatable valve's valve positions is separated by a quarter turn.
 17. The apparatus of claim 15, wherein the ratio between the range of travel of each barbell support and the range of push-rod travel is about 2:1.
 18. The apparatus of claim 15, further including an enclosure for said accumulator tank and said hydraulic cylinder, said enclosure extending between said uprights.
 19. The apparatus of claim 15, further including a single check valve between said actuatable valve and said hydraulic cylinder, wherein said single check valve only allows hydraulic fluid to flow into said hydraulic cylinder.
 20. The apparatus of claim 15, wherein said at least one valve actuator is positioned for access by a user's foot when the user is on said bench. 